The content of free and bound inositol in human and cow's milk.

The gaschromatographic method was used for the quantitative analyses of inositol in milk. The content of inositol in human and cow's milk at the different lactation periods was determined. The content of total myoinositol in human milk was 32.7 plus or minus 15.2 mg/100 ml in colostrum, 17.8 plus or minus 1.9 mg/100 ml in transitional milk, and 14.9 plus or minus 3.1 mg/100 ml in mature milk. In cow's milk, it was 10.6 plus or minus 1.0, 7.0 plus or minus 1.1, and 4.1 plus or minus 1.0 mg/100 ml, respectively. These values were very similar to those obtained by the microbiological method. The presence of lipid-bound myoinositol in both kinds of milk was confirmed and the content was 0.22 plus or minus 0.09 mg/100 ml in human milk and 0.36 plus or minus 0.10 mg/100 ml in cow's milk. A small amount of scylloinositol was found in both human and cow's milk, while dextroinositol was not found in either.